Extracellular vesicle lipidomics reveals active lipid flux remodelling in coronary artery disease beyond statin therapy
S Fathieh, M P Gray, S M Grieve, G A FigtreeAbstract
Background
Conventional lipid biomarkers do not fully capture the dynamic lipid remodelling underlying atherosclerosis. Extracellular vesicles (EVs) provide a direct readout of cellular lipid trafficking, but their relevance to coronary artery disease (CAD) and modulation by clinical factors remains unclear.
Purpose
To define CAD-specific EV lipid signatures, disentangle covariate effects, and identify underlying lipid metabolic pathways.
Methods
We performed high-resolution LC–MS lipidomics of plasma EVs in 620 BioHEART-CT participants (415 CAD, 205 no CAD). After quality control, 359 lipid species were analysed. Multivariable models and pathway-based network analysis were used to separate CAD-specific signals from the effects of age, sex, and statins.
Results
The EV lipidome robustly discriminated CAD status , driven predominantly by triacylglycerols and sphingomyelins, indicating enrichment of energy-storage and membrane lipids. Importantly, CAD was characterised by coordinated remodelling of lipid flux rather than isolated lipid changes. Pathway analysis demonstrated upregulation of cholesterol esterification and phosphatidylcholine turnover, alongside suppression of diacylglycerol-to-triacylglycerol storage and sphingomyelin-to-ceramide pathways, consistent with enhanced membrane remodelling and reduced lipid storage. Age and sex introduced modest but structured variation, primarily affecting phosphatidylcholine and sphingolipid species, while statin therapy induced targeted remodelling of phospholipid pathways, including depletion of phosphatidylinositols and activation of PLA2- and CEPT1-mediated PC/PI→DG→PE/LPE cascades. Lipid signatures specific to CAD remained evident even after adjusting for all covariates, suggesting that EV lipidomics reflects disease biology beyond what is explained by traditional risk factors and lipid-lowering treatments.
Conclusion
EV lipidomics identifies a distinct, pathway-level signature of coronary artery disease characterised by active lipid remodelling and cholesterol handling, which is not captured by conventional lipid measures and persists despite statin therapy. These findings position EV lipidomics as a functional biomarker of vascular lipid metabolism with potential applications in risk stratification and therapeutic monitoring.
Figure 1 - EV lipid pathway activity network. Key upregulated routes include cholesterol esterification (Chol -> CE), PE -> LPC, and TG -> DG -> PA -> PC/LPC, implicating SOAT, PLA2, PLD, DGK, and lipase families in CAD-associated EV lipid reprogramming.Figure 1